A high-quality genome of Actinidia eriantha provides new insight into ascorbic acid regulation

Actinidia eriantha is one of the species of kiwifruit with a particularly high ascorbic acid (AsA) content.However, the molecular mechanism driving AsA richness in fruit remains unclear.In order to reveal the molecular mechanism of AsA richness in A. eriantha, this study constructed a regulatory network related to AsA metabolism by combining genomics,metabolomics and transcriptomics.We assembled a high-quality genome of A. eriantha ‘Ganlv 1’ with only five remaining gaps.The assembly is comprised of 29 pseudochromosomes with a total size of 615.95 Mb, and contig N50 of 20.35 Mb.Among them,24 of the pseudochromosomes were obtained directly from telomere-to-telomere.The LTR assembly index score and consensus quality value were 21.34 and 39.90%, respectively.Subsequently, 61 metabolites and 2 092genes were found to be differentially accumulated/expressed during fruit development by metabolome and transcriptome assays, respectively.AsA metabolism and the cyclic regeneration pathway were found to have high expression levels throughout fruit growth and development,suggesting its crucial role in the regulation of AsA.Furthermore,the AsA contents are highly associated with ascorbate peroxidase genes.The genome obtained in this study provides genomic resources for the genetic and breeding research ofA. eriantha, and the constructed regulatory network can provide a public data platform for future research on kiwifruit.

Appraisal of Improvement in Physiological and Metabolic Processes by Exogenously Applied Natural and Synthetic Ascorbic Acid in Okra(Abelmoschus esculentus L.)Fruit Subjected to Water Deficit Stress

To counteract the effects of drought stress,scientists have adopted several approaches including the use of different chemicals both inorganic and organic,which is contemplated as a highly efficient and cost-effective shot-gun approach.Ascorbic acid(AsA)is a potential organic substance,which widely occurs in plants,and is considered to be an effective antioxidant to counteract reactive oxygen species(ROS).Thus,a pot experiment was performed to assess the relative mitigating impacts of synthetic AsA and naturally occurring AsA in the form of lemon juice(LJ)and orange juice(OJ)on two cultivars of okra(Abelmoschus esculentus L.)namely Sabz Pari and Bhindi Sanwali under varying water deficit conditions.After 30 days of seed germination,okra seedlings were subjected to different irrigation regimes,i.e.,water deficit stress[(65%and 50%F.C.)and control conditions(100%F.C.)].Different levels of AsA[control(no spray),14 mg L^(−1)LJ,24 mg L^(−1)OJ and 150 mg L^(−1)AsA]obtained from different sources were applied as a foliar spray to control and water-stressed plants.Drought stress prominently reduced plant growth and yield attributes of the okra cultivars.Water-deficit conditions(65%and 50%F.C.)substantially decreased the fruit chlorophyll(a,b)pigments and the activity of superoxide dismutase(SOD)enzyme,while an increase was observed in the contents of fruit’s hydrogen peroxide(H_(2)O_(2)),malondialdehyde(MDA),total phenolics,total soluble sugars,AsA,and total soluble proteins.Drought stress also increased the activities of antioxidant enzymes like peroxidase(POD)and catalase(CAT).However,plant growth and yield attributes,fruit chlorophyll pigments,total phenolics,total soluble sugars,total free amino acids,total soluble proteins,AsA,GB,H_(2)O_(2),and the activities of antioxidant enzymes(POD and CAT)were increased by the AsA exogenous treatment in both okra cultivars under water deficit and control conditions.Overall,LJ and OJ were more effective than the synthetic AsA in upregulating the physiological and metabolic processes of okra plants.So,cost-effective as well as multi-nutrient natural sources of AsA could be suggested for alleviating the harmful effects of water deficit stress on plants.

The Protective Effect of Ascorbic Acid and Thiamine Supplementation against Damage Caused by Lead in the Testes of Mice

Lead is a ubiquitous environmental and industrial pollutant that may have toxic effects on the male. Vitamins may protect against toxic effects of lead in the liver and reproductive system, which is confirmed by our initial research. The aim of this study was to further investigate the protective effects of vitamins （ascorbic acid combined with thiamine） on lead acetate （Pb）-induced reproductive toxicities in mice and study the possible mechanisms underlying these effects. Forty-five male mice were randomly divided into 3 groups, 15 mice in each and received daily intragastric administration with control, Pb （20 mg/kg）, and Pb＋vitamins （ascorbic acid of 420 mg/kg＋thiamine of 30 mg/kg） for 6 weeks, respectively. The Pb-treated animals showed significant decreases in the epididymal sperm count and motility compared to the control group, while the Pb＋vitamins group had significant increases for these variables. Moreover, an increasing apoptosis of germinal cells induced by Pb was reduced by vitamin treatment. Pb induced the activation of Caspase-3, Fas/Fas-L and Bcl-2 with elevated levels, and the adaptor protein primarily regulated signaling through Fas and required for Fas-induced apoptosis. In conclusion, ascorbic acid combined with thiamine exhibited protective effect on reproductive system by inhibiting Pb-induced excessive cell apoptosis.

Formation of a cerium conversion coating on magnesium alloy using ascorbic acid as additive.Characterisation and anticorrosive properties of the formed films

Cerium-based conversion coatings were formed on AZ91D magnesium alloy by immersion of the substrate in solutions containing Ce(NO_(3))_(3),H_(2)O_(2) and ascorbic acid(HAsc).The characterisation of the films was performed by electrochemical and surface analysis techniques such as SEM,EDS,X-ray diffraction and X-ray photoelectron spectroscopy(XPS).The degree of corrosion protection achieved was evaluated in simulated physiological solution by the open circuit potential monitoring,polarisation techniques and electrochemical impedance spectroscopy(EIS).The presence of HAsc in the conversion solution causes changes in the morphology,adherence and anticorrosive performance of the films.The improvement in the corrosion resistance is closely associated with the corrosion inhibition properties of HAsc.

Effect of Storage Conditions on the Sensory Quality, Colour and Texture of Fresh-Cut Minimally Processed Cabbage with the Addition of Ascorbic Acid, Citric Acid and Calcium Chloride

The aim of this study was to investigate the effect of storage conditions on the sensory quality, colour and texture of fresh-cut cabbage during the addition of ascorbic acid, citric acid and calcium chloride. Ascorbic acid maintained the overall quality for 14 days at 0℃ and 7 days at 5℃;no difference, however, was observed regarding browning of cut surface compared to the control sample at both storage temperatures. Calcium chloride maintained the overall quality and cut surface browning for 14 days at both storage temperatures. It was also found that citric acid 1% can be used for minimally processed cabbage. Soaking with citric acid helped retain the color and increased the overall acceptance and organoleptic quality of fresh cut cabbage;it reduced browning of the cut surface and protected against formation of black specks. Citric acid treatment combined with low temperature storage (0℃) prolonged the shelf life of minimally processed cabbage for 22 days, time sufficient for acceptable marketing of the product. The lightness of minimally processed cabbage decreased linearly from 70.94 ± 6 to 63.8 ± 8.5 - 61.3 ± 8 units for the chemical treatments during 22 days of storage at 0℃. Hue angle values during storage time were also significantly influenced by chemical treatments mainly at 0℃.

Facile Synthesis of Gold Nanoparticle-loaded Carbon Nanofiber Composites and Their Electrocatalytic Activity Towards Dopamine, Ascorbic Acid and Uric Acid

A facile approach for the synthesis of gold nanoparticle-loaded carbon nanofiber（Au/CNF） composites was developed. When applied to electrochemistry, these composites showed attractive performances such as high conductivity and facile electron transfer kinetics. Under physiological conditions, the Au/CNF composite modified electrode exhibits highly electrocatalytic activity for the oxidation of dopamine, ascorbic acid and uric acid. Owing to the good selectivity for the simultaneous detection of these three species, the novel composites are promising for the development of effective electrochemical biosensors.

Aluminum Contents in Dry Leaves and Infusions of Commercial Black and Green Tea Leaves: Effects of Sucrose and Ascorbic Acid Added to Infusions

Tea consumption has increased due to its beneficial effects. Results from a lab study on the effect of sucrose (5 g per cup, 150 mL) and/or ascorbic acid (2 mL per cup, 150 mL) on dissolved aluminum compounds during the infusion of two commercial types of dry tea leaves (black, green) with boiling water (5, 15 min infusion time) are presented. Factors influencing the presence of dissolved aluminum in the infusions of both tea leaves were infusion time and sugar contents, as well as the interaction between ascorbic acid and sucrose (p < 0.05). Aluminum contents found after 15 min of infusion were 0.7 mg L–1 for black tea infusions added with sugar, and 0.69 mg L–1 for green tea added with both sugar and ascorbic acid. Both concentrations are higher than the level accepted in Mexico for drinking water (there is no act concerning tea infusions), that is 0.2 mg L–1.

Food Additives-Ascorbic Acid Quality Assay Test Intelligent Management

In this paper, based on the analysis and test methods of national standards （GB 14754-2010） and chemical analysis and test items carried out by chemical enterprises, a set of automatic processing of quality analysis test data of ascorbic acid products was developed by using access database technology and Visual Basic programming language system, and its stability was investigated. The results show that the software can manage intelligently all aspects of the quality analysis and test of ascorbic acid products, uploading timely the data and results of the analysis and inspection to the network and saving it for users, enterprises and quality management, which set up a network of information sharing platform to ensure the authenticity and reliability of measurement results, improving greatly the speed of data processing, saving valuable time, reducing production costs with good economic efficiency and social benefit. It has practical value for ascorbic acid quality analysis test data processing automatically the results of the implementation of intelligent management.

RADIATION EFFECT ON BIOSYNTHESES OF ASCORBIC ACID AND RIBOFLAVIN IN GERMINATING CHICKPEA

The influence of irradiation on biosyntheses of ascorbic acid and riboflavin in germinating chickpea seeds at ambient (25-35℃) conditions, was investigated. The rate of syntheses of these vitamins significantly increased with increasing germination time upto 120 h depending upon the treatment (P【0.05). Maximum amounts of ascorbic acid, 22.32 and 16.84 mg/100g, were found in the 0.10 kGy sample after 120 h of germination in tap and distilled water respectively. However, a radiation dose of 0.15 kGy resulted in the development of maximum values of riboflavin, 11.40 and 11.38 μ g/g, on germination in tap and distilled water respectively. A significant linear relation (r = 0-954 to 0.997) was observed between the biosyntheses of these vitamins and the germination time upto 120 h of irradiated and unirradiated chickpea seed (P【0.05).

EFFECT OF ASCORBIC ACID ON DNA SYNTHESIS,INTRACELLULAR ACCUMULATION OF ADM AND ADM RESISTANCE OF TUMOR CELL LINES

Objective: To determine the effect of ascorbic acid (AA) on DNA synthesis, intracellular accumulation of ADM and ADM resistance of tumor cell lines. Methods: K562, K562/ADM and KB cell lines were used to study the effect of ascorbic acid on DNA synthesis, intracellular accumulation of ADM and ADM resistance by fluid scintillometry, MTT method, spectrofluorophotometry and immunocytochemistry. Results: Results showed that AA was capable of inhibiting DNA synthesis of K562 and K562/ADM in a dosedependence fashion, but not KB cell line, and significantly reducing ADM sensitivity in K562 and KB cell lines, as well as potentiating obviously ADM resistance in K562/ADM cell line. Conclusion: These effects of AA may be closely correlated with significant elevation of intracellular accumulation of ADM in KB cell line, and significant reduction of that in K562 and K562/ADM cell lines but possibly not correlated with the expression of Pglycoprotein.

Ascorbic acid and curcumin alleviate abnormal estrous cycle and morphological changes in cells induced by repeated ultraviolet B radiations in female Wistar rats

Objective: To study the protective effect of ascorbic acid and curcumin against the abnormal estrous cycle and morphological changes in cells induced by repeated ultraviolet B(UVB)radiation in female Wistar rats.Methods: Sixteen female sexually mature Wistar rats weighing 130-150 g and aged 12-16 weeks were randomly divided into four groups.The control group received normal food and water ad libitum.The UVB group was exposed to a dose of 280 nm of UVB radiation for 2 h daily.The UVB+curcumin group received a dose of 280 nm of UVB radiation for 2 h daily and also an oral dose of curcumin(25 mg/kg body weight)daily.The UVB+ascorbic acid group received a dose of 280 nm of UVB radiation for 2 h daily and also an oral dose of ascorbic acid(250 mg/kg body weight)daily.All the treatments last for 15 consecutive days.Body and ovary weight and gonadosomatic index were measured.The stages(proestrus,estrus,metaestrus and diestrus)of the estrous cycle were determined by the cell types observed in the vaginal smear.Results: UVB radiation caused irregular alterations on the estrous cycle and morphological changes of the female Wistar rat as compared with the control group.Ascorbic acid and curcumin protected UVB-induced estrous phases and their cells.But curcumin showed greater protection than ascorbic acid.Conclusions: Ascorbic acid and curcumin at low doses can alleviate abnormal estrous cycle and morphological changes in cells induced by UVB radiations in female Wistar rats.

Topical Application of Ascorbic Acid Solution as an Adjunctive Method of Periodontal Therapy among Wet Snuff Users after Prosthodontics Therapy

Background: During several years, ascorbic acid (vitamin C) played a significant role in the health of periodontal tissues. The goals of prosthodontics management are to restore the missing teeth, provide the loss of teeth functions, and establish acceptable dental esthetics, and there are some evidences revealing the passive effects of snuff on the results of prosthodontics and periodontal treatment, so the present study is performed to evaluate the outcomes of topical application of ascorbic acid solution as an adjunctive method of periodontal therapy among wet sniff users after prosthodontics therapy. Methods: The clinical situation was evaluated in 150 moderate periodontitis patients after conventional periodontal and prosthodontics therapy. They were selected from outpatient clinics, college of dentistry, King Khalid University, and from some hospitals Ministry of Health in Tabuk, Jazan and Aseer regions. The study was conducted from September 2020 to December 2020. The time of post-treatment assessment was one year. The study was included 50 patients who don’t use wet snuff as a group I (GI) (control group), 50 patients wet snuff users as group II (GII), and 50 patients wet snuff users were treated with topical application of ascorbic acid solution as group III (GIII). The participants were aged over 20 years, with a mean age of 35 years. The duration of using wet snuff was at least one year. Plaque index (PLI), gingival index (GI), clinical attachment loss (CAL) were recorded at baseline (first visit), then after 4 weeks (second visit) and after 6 weeks (third visit) of conventional periodontal therapy and topical application of ascorbic acid solution. Statistical analysis was done using ANOVA test and paired t-test. Results: According to statistical analysis, there was the inclination of decrease in the mean and standard deviation of plaque index (PLI) from 2.8 ± 1.4 to 2.5 ± 0.51, and 2.7 ± 0.33 in group II, and decrease from 2.7 ± 0.34 to 2.5 ± 0.23 and 2.6 ± 0.65 in group III. Similarly in the gingival index (GI), there was a decrease in the mean and standard deviation from 2.8 ± 0.52 to 2.3 ± 0.62 and 2.5 ± 0.51 in group II and a decrease from 2.5 ± 0.8 to 2.3 ± 0.58 and 2.4 ± 0.47 in group III. Moreover, there was a decrease in the mean and standard deviation of clinical attachment loss (CAL) from 4.5 ± 0.26 to 3.9 ± 0.83 and 4.2 ± 0.83 in group II and from 4.2 ± 0.31 to 3.8 ± 0.46 and 3.8 ± 0.31 in group III;less than group I without significance differences (p > 0. 05) in all study groups at baseline and after 4 weeks, and 6 weeks of follow up except CAL. Conclusion: The results of our study displayed that periodontal parameters vary among wet snuff users after topical application of ascorbic acid solution as an adjunctive method of periodontal therapy

The Effects of Calcium Chloride and Ascorbic Acid Treatment on Ready-to-use Carrot Shreds

This study aimed to evaluate the effect of calcium and ascorbic acid treatments on the quality of carrot shreds during storage. Towards this aim, carrot shreds were dipped into a 5 L solution of 2 g/L ascorbic acid containing 1%, 3%, or 5% CaCI2 （Ca ＋ AA） for 3 min at room temperature （-20 ℃）. In case of the control group （control, C）, samples were dipped into distilled water for the same time interval. Subsequent to treatment, carrot shreds were stored in a cold room at 5 ± 1 ℃, 85-90% RH for a period of 11 days. Color values （L＊, a＊ b＊）, whiteness index, saturation index, hue angle values, visual quality, firmness scores, bitterness scores, total soluble solids （TSS） and electrolyte leakage measurements were conducted at various sampling dates. The results from this study demonstrated that brightness of carrot shreds was augmented by calcium and ascorbic acid treatments irrespective of the dosage used. Whiteness index values for the 5% Ca ＋ AA treated samples were observed to be low whereas saturation indices of 5% Ca ＋ AA and 3% Ca ＋ AA treated carrot shreds were higher as compared to other treatments. This study concludes that treatment with calcium at high doses improves the color quality of carrot shreds under storage conditions. Visual quality and firmness of carrot shreds was maintained till day 4 of storage, thereafter it declined as compared to the control group, Bitterness of carrot shreds was also observed to increase upon treatment with calcium and ascorbic acid. However, calcium treatment of the test carrot shreds was seen to decrease weight loss and cause an increase in the TSS under storage conditions.

Lead Induced Disorders in Hematopoietic and DrugMetabolizing Enzyme System and Their Protection by Ascorbic Acid Supplementation

Effect of vitamin C supplementation in restoring lead induced alterations in hematopoietic system and drug metabolizing enzymes were investigated in male rats. Intraperitoneal administration of 20 mg/kg lead produced a significant inhibition of heme synthesis in blood and liver and drug metabolism in liver. Toxic insult by lead also resulted into a marked decline in tissue thiols and vitamin C levels. Oral supplementation of vitamin C (100 mg/kg for 3 days) completely restored blood delta aminolevulinic acid dehydratase, uroporphyrinogen I synthetase and a few drug metabolizing enzymes. Level of vitamin C and sulfhydryl contents too recovered to a great extent. A marked reduction in blood and liver lead concentration occurred on vitamin C supplementation although renal lead contents were marginally reduced in lead exposed animals. The results, thus, indicate a significant protective action of vitamin C against toxic effects of lead on heme synthesis and drug metabolism.

Preparation of Cu nanoparticles with ascorbic acid by aqueous solution reduction method

Cu nanoparticles were prepared by reducing Cu2＋ ions with ascorbic acid through aqueous solution reduction method. The effects of solution pH and average size of Cu2O particles on the preparation of Cu nanoparticles were investigated. Cu particles were prepared at pH 3, 5 or 7, with the smallest Cu particles obtained at pH 7. However, Cu particles could not be prepared at pH 9 or 11. The average size of Cu2O particles can affect that of Cu particles. Larger Cu2O particles result in larger Cu particles. In addition, experiments were conducted to explore the reaction process by measuring the X-ray diffraction （XRD） patterns of specimens collected at different time points during the reaction. It was found that Cu（OH）2 was initially formed as a precursor, followed by the formation of Cu2O, which was finally reduced to Cu particles.

VOLTAMMETRIC BEHAVIOR OF ASCORBIC ACID AT α-CYCLODEXTRIN INCORPORATED CARBON NANOTUBES-COATED ELECTRODE

制备了α -环糊精掺杂纳米碳管涂层电极并应用于抗坏血酸的电催化氧化 ,结果表明 ,氧化电位降低了 2 80mV ,电流响应明显增加。我们首次结合两种物质的特性 :纳米碳管的导电性及催化性能、α -环糊精的分子认知能力 ,对电极表面进行修饰。实验了抗坏血酸与α -环糊精超分子络合物的特性。差示脉冲技术用于定量分析抗坏血酸 ,线性范围为 2 .5× 10 -6～ 1.0× 10

Ascorbic Acid Promotes Arsenic-induced Cytotoxicity in Human Hepatocarcinoma Cells and Their Underlying Mechanisms

Objective: To study synergistic effect with Ascorbic acid(AA) on arsenic trioxide inducing human Hepatocarcinoma cell apoptosis, and provide theoretical basis for promoting human Hepatocarcinoma cell apoptosis induced by arsenic trioxide(AT). Methods: Human Hepatocarcinoma cell line BEL-7402 being cultured in vitro, the effect of AT and (or) AA on its growth inhibition and its two intracellular signal molecules was evaluated separately using MTT and Western blot. Results: AT at a few μmol/L concentration could suppress abnormal proliferation of human hepatocarcinoma cells, and initiate their apoptosis by activation of caspase-3, and activate extracellular-signal regulated kinases (ERKs), which were dependent on the dosage of AT conspicuously. The effect of AA on BEL-7402 was not significant; However, AA could effectively enhance AT-induced hepatocarcinoma cell apoptosis and lesion severity through activation of caspase-3 but not ERKs. Conclusion: Caspase-3 and ERKs proteins could involve in arsenic-induced hepatocarcinoma cell apoptosis and differentiation respectively as intracellular signaling molecules; The effect between AT and AA on hepatocarcinoma is synergistic, which further inhibits cell growth and induces apoptosis in human hepatocarcinoma cells through activation of caspase-3 but not ERKs.

Effect of Ascorbic Acid and Silicium on Photosynthesis, Antioxidant Enzyme Activity, and Fatty Acid Contents in Canola Exposure to Salt Stress

The effects of exogenous ascorbic acid and silicium on leaf fresh weigh, seed yield, photosynthesis, changes of the activities of major antioxidant enzymes, nitrate reductase activity, proline accumulation, chlorophyll content, and fatty acid composition were investigated in salt-stressed canola. A hydroponic pot experiment was conducted based on randomized complete block design, factorial arrangement was used with 16 combinations of salinity stress （0, 100, 200, and 300 mmol L-1 NaC1）, ascorbic acid （0 and 30 mmol L-1）, and silicium （2 and 4 mmol L-1 from potassium silicate） with three replicates. The results showed that salinity significantly decreased leaf area and leaf fresh weight, seed yield, photosynthesis, nitrate reductase activity, chlorophyll content, and seed protein percentage. Conversely, respiration, antioxidant enzymes activity, proline accumulation, and linolenic acid percentage increased due to salt stress. Ascorbic acid application improved photosynthesis and seed yield and mitigated antioxidant enzyme activity. In addition, nitrate reductase activity and chlorophyll a and b were positively affected by ascorbic acid. Regarding silicium application, that was found that leaf area, leaf fresh weight, seed yield and photosynthesis, ascorbate peroxidase activity, nitrate reductase activity, and chlorophyll content increased, while respiration decreased. Furthermore, silicium had not significant effect on antioxidant enzyme activity. In general, ascorbic acid and silicium were involved in the defensive mechanisms against salinity stress and it can be suggested that, ascorbic acid and silicium application had positive effect on canola growth under conditions of salt stress.

Protective effect of ascorbic acid on cyclophosphamide induced testicular gametogenic and androgenic disorders in male rats

Aim:To study the detrimental effects of cyclophosphamide on the testicular androgenic and gametogenic activities through endocrine inhibition and/or induction of oxidative stress in male albino rats and to evaluate the protective effect of ascorbic acid.Methods:The testicular△^(5),3β-hydroxysteroid dehydrogenase(HSD),17β-HSD,peroxidase and catalase activities along with the levels of malondialdehyde(MDA)and conjugated dienes in testicular tissue were measured for the evaluation of testicular oxidative stress.The plasma testosterone(T)level was measured by immunoassay.Various germ cells at stageⅦof spermatogenic cycle were quantified from testicular stained sections.Results:Cyclophosphamide treatment results in a significant inhibition in the testicular△^(5),3β-HSD and 17β-HSD activities,a decrease in plasma T level and a diminution in the counts of various germ cells.Moreover,this treatment was also associated with a significant inhibition of the peroxidase and catalase activities along with high levels of MDA and conjugated dienes in the testis.All these changes were reversed by ascorbic acid co-administration.Conclusion:Cyclophosphamide treatment at the dosage used caused testicular gametogenic and androgenic disorders as well as induced testicular oxidative stress that can be reversed by ascorbic acid co-administration.

Low-volume plus ascorbic acid vs high-volume plus simethicone bowel preparation before colonoscopy

AIM： To investigate the effectiveness of low-volume plus ascorbic acid [polyethylene glycol plus ascorbic acid （PEG ＋ Asc）] and high-volume plus simethicone [polyethylene glycol plus simethicone （PEG ＋ Sim）] bowel preparations. METHODS： A total of one hundred and forty-four outpatients （76 males）, aged from 20 to 84 years （median age 59.5 years）, who attended our Department, were divided into two groups, age and sex matched, and underwent colonoscopy. Two questionnaires, one for patients reporting acceptability and the other for endoscopists evaluating bowel cleansing effectiveness according to validated scales, were completed. Indications, timing of examination and endoscopical findings were recorded. Biopsy forceps were used as a measuring tool in order to determine polyp endoscopic sizeestimation. Difficulty in completing the preparation was rated in a 5-point Likert scale （1 = easy to 5 = unable）. Adverse experiences （fullness, cramps, nausea, vomiting, abdominal pain, headache and insomnia）, number of evacuations and types of activities performed during preparation （walking or resting in bed） were also investigated. RESULTS： Seventy-two patients were selected for each group. The two groups were age and sex matched as well as being comparable in terms of medical history and drug therapies taken. Fourteen patients dropped out from the trial because they did not complete the preparation procedure. Ratings of global bowel cleansing examinations were considered to be adequate in 91% of PEG ＋ Asc and 88% of PEG ＋ Sim patients. Residual Stool Score indicated similar levels of amount and consistency of residual stool; there was a significant difference in the percentage of bowel wall visualization in favour of PEG ＋ Sim patients. In the PEG ＋ Sire group, 12 adenomas≤ 10 mm diameter （5/left colon ＋ 7/right colon） vs 9 （8/left colon ＋ 1/right colon） in the PEG ＋ Asc group were diagnosed. Visualization of small lesions seems to be one of the primary advantages of the PEG ＋ Sim preparation. CONCLUSION： PEG ＋ Asc is a good alternative solution as a bowel preparation but more improvements are necessary in order to achieve the target of a perfect preparation.